Now I’ve decided to try to construct a more robust flyback secondary, using the experience from the previous setup that you can see here.
The windings are very close and tight, aprox. 60 turns per layer. The ending wire is insulated and brought back to the start side before a new layer is constructed. Also oil is added over the turns to fill some of the air gaps:
I’ve wired arround 7 layers for a total of aprox. 400 turns. To test the flyback I’ve used my high power ZVS driver (with a 6.6uF/630V capacitor):
I’ll need some extra turns for higher voltage, but the current is good. I’ve used 0.4mm CuEm wire.